Synthroid Uses, Dosage & Side Effects

Additional laboratory testing and clinical findings may be necessary. Biochemical assessment incorporated measurement of serum TSH, T3, and T4. TSH lower limit of quantification was 0.2 mIU/L and upper limit of normal was 5.6 mIU/L, as indicated by the shaded area.

DOSAGE AND ADMINISTRATION

• Generally, thyroid replacement treatment is to be taken for life.
• Triiodothyronine (T3) and L-thyroxine (T4) diffuse into the cell nucleus and bind to thyroid receptor proteins attached to DNA.
• Do not share this medicine with another person, even if they have the same symptoms you have.
• Take levothyroxine tablets and capsules on an empty stomach, at least 30 to 60 minutes before breakfast with a full glass of water.
• These medications are those where small changes in the dose or blood concentration may lead to serious therapeutic failures and/or adverse drug reactions.
• Start at a lower starting dosage and increase the dosage every 4 to 6 weeks as needed based on clinical and laboratory response.

Grapefruit juice may delay the absorption of levothyroxine and reduce its bioavailability. Titrate the dose of SYNTHROID carefully and monitor response to titration to avoid these effects see Dosage and Administration (2.4). Consider the potential for food or drug interactions and adjust the administration or dosage of SYNTHROID as needed see Dosage synthroid confusion and Administration (2.1), Drug Interactions (7.1), and Clinical Pharmacology (12.3).

Knowing that patient behaviors and consistency of treatment are key factors in treatment success, I educate patients on the process as they begin treatment. The importance of writing “Dispense as Written,” or using the state-specific language for SYNTHROID, is something I discuss with my staff as well. The FDA has determined that drugs that are classified as therapeutically equivalent can be substituted with the full expectation that the substituted product will produce the same clinical effect and safety profile as the reference product.

Antidepressant Therapy

Monitor patients receiving concomitant SYNTHROID and sympathomimetic agents for signs and symptoms of coronary insufficiency. Levothyroxine belongs to a class of medications called hormones. It works by replacing thyroid hormone that is normally produced by the body. There are certain populations where we pay closer attention to thyroid medication dosing.

Because some preparations of the drug may contain iodine or lactose, patients should tell their doctors about such allergies or reactions to these components. Hypersensitivity reactions to inactive ingredients have occurred in patients treated with thyroid hormone products. These include urticaria, pruritus, skin rash, flushing, angioedema, various gastrointestinal symptoms (abdominal pain, nausea, vomiting and diarrhea), fever, arthralgia, serum sickness, and wheezing. SYNTHROID is indicated in adult and pediatric patients, including neonates, as an adjunct to surgery and radioiodine therapy in the management of thyrotropin-dependent well-differentiated thyroid cancer.

Related/similar drugs

In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15%to 20%, respectively. To minimize the risk of hyperactivity, start at one-fourth the recommended full replacement dosage, and increase on a weekly basis by one-fourth the full recommended replacement dosage until the full recommended replacement dosage is reached. Start at a lower starting dosage and increase the dosage every 4 to 6 weeks as needed based on clinical and laboratory response. Synthroid (levothyroxine) treats hypothyroidism (low thyroid hormone) and different types of … Following a 25-mcg dose change of levothyroxine, most patients had changes in TSH levels. Personally, I have had experiences where I have written for brand-name SYNTHROID and the patients have been dispensed generic levothyroxine or even another branded levothyroxine product.

Enter medications to view a detailed interaction report using our Drug Interaction Checker. You should not use levothyroxine if you are allergic to glycerin or edetate disodium, or if you have an untreated or uncontrolled adrenal gland disorder. Use the drop-down menu below to select your state and see the specific language required to prevent generic substitution.

Drugs That May Decrease Conversion of T4 to T3

I review with the patients the important issues about how to take the medication, as consistency is really the key message. I talk about the fact that it’s important to take the medication in the same timing and pattern each day, take it on an empty stomach minutes before they eat. I also review the safety and risks of taking thyroid medication.

Serum TSH levels should be monitored and the SYNTHROID dosage adjusted during pregnancy. Since postpartum TSH levels are similar to preconception values, the SYNTHROID dosage should return to the pre-pregnancy dose immediately after delivery see Dosage and Administration (2.3). Thyroid hormones exert their physiologic actions through control of DNA transcription and protein synthesis. Triiodothyronine (T3) and L-thyroxine (T4) diffuse into the cell nucleus and bind to thyroid receptor proteins attached to DNA.

Stop biotin and biotin-containing supplements for at least 2 days before assessing TSH and/or T4 levels see DRUG INTERACTIONS. Patients The SYNTHROID dosage is based on the target level of TSH suppression for the stage and clinical status of thyroid cancer. Concurrent use of tyrosine-kinase inhibitors such as imatinib may cause hypothyroidism. Monitor serum free-T4 levels and maintain in the upper half of the normal range in these patients. The SYNTHROID dosage is based on the target level of TSH suppression for the stage and clinical status of thyroid cancer. Take levothyroxine tablets and capsules on an empty stomach, at least 30 to 60 minutes before breakfast with a full glass of water.